A Christian County broiler flock of 22,000 hens has been culled after birds tested positive for avian influenza.

The confirmation of H7N9 is the same low pathogenic bird flu strain found in Tennessee, but it can’t be directly linked according to Kentucky State Veterinarian Dr. Robert Stout. “There is no epidemiologic link to Tennessee, the best guess is that it's in the environment from contamination from wild waterfowl, who are a reservoir for avian influenza.”

Murray State University Breathitt Veterinary Center in Hopkinsville detected the H7N9 strain while conducting a routine pre-slaughter test last week. The test is for "spent hens" at the end of their laying cycle before being slaughtered for meat.

Stout said the hens were 'asymptomatic' with no clinical signs of disease. The strain poses no health risks to humans. The strain is different then the high-pathogenic outbreaks in Asian countries, which can cause severe disease with high mortality.

The bird flu is not transferred through eggs or meat consumption, Stout said.

Stout said the OSV and USDA Animal and Plant Health Inspection Service are conducting surveillance on flocks within a six-mile radius of the affected farm.

Stout would not confirm which company the farm had an affiliation with. A similar outbreak at farm in Tennessee were contracted with Tyson. Those flocks have been 'depopulated' and are not in the food supply.

Poultry producers and bird owners are urged to take biosecurity measures to prevent the spread of influenza. Measures include isolating birds from visitor and others, keeping equipment and vehicles clean, watch for signs and report sick birds.

"The support that we get from our laboratories from UK and in this case from the Breathitt Veterinary Center associated with Murray State is critical to our response and they've been very, very responsive. Certainly the companies and USDA along with KDA have a very strong partnership that work cooperatively to address these issues as quickly as we can," Stout said.

The last bird flu outbreak in 2009 was also isolated cases found in western Kentucky. The affected premises is under quarantine. There was another outbreak in 2015, primarily in Iowa and Minnesota.

Poultry and eggs generated an estimated $1.2 billion in cash receipts to Kentucky farmers in 2015. Farmers in the commonwealth produced 307.7 million broilers and nearly 1.3 billion eggs in 2015.

Authorities are closing live poultry markets in multiple Chinese cities and provinces, in an effort to stop the spread of the deadly H7N9 strain of the avian flu virus.

"Officials in the southern Chinese city of Guangzhou – population 17 million – found more than 30 percent of the city's poultry markets are contaminated with the H7N9 strain of bird flu," as NPR's Rob Schmitz reports from Shanghai.